Bullying, sexual violence, and dating aggression are all major public health problems that occur at relatively high rates and demand attention to alleviate the suffering they cause (CDC, 2004;Holt &Espelage, 2005). These problems undoubtedly share developmental correlates and evidence is emerging that these problems co-occur among early adolescents (for review Espelage &Horne, 2007). Research has demonstrated that problem behaviors, including bullying, tend to be interrelated and share common risk factors (Jessor, 1991), suggesting the need for prevention programs that implement a coordinated set of interventions to target and reduce overlapping risk factors rather than programs that focus on specific problems or separate disorders (Kenny et al., 2002). Despite common underlying risk factors, the development of bullying and sexual violence programs have remained largely divorced from each other- creating more burden and cost for schools. This study proposes a large-scale, randomized longitudinal evaluation of Second Step: Student Success Through Prevention (Second Step - SSTP), a middle school intervention (Committee for Children, 2008), which targets the shared underlying risk and protective factors for bullying, sexual harassment, and dating aggression. This program is unique in its emphasis on the role of peer group norms, attitudes, and behavior in the initiation and maintenance of bullying and other forms of violence. Because of this, this investigation will involve a direct test via social network analysis the extent to which peer norms or shifts in peer attitudes are impacted by the intervention. Bullying is conceptualized as including verbal, physical, relational, and cyber-aggression. Sexual violence is conceptualized as including sexual harassment, sexual coercion in dating relationships, and homophobic teasing. Thirty-two schools (five to six 6th grade classrooms per school yielding sample of 4,800 students) will be drawn from two school districts in Illinois and one large district in Wichita, Kansas and randomly assigned to Second Step - SSTP or a control condition. Second Step - SSTP program draws from the risk/protective factors model and social-cognitive theories of aggression. Lessons focus on the outcomes of bullying, relational aggression, sexual harassment, dating relationships, and substance use. Risk factors targeted include inappropriate classroom behavior, favorable attitudes toward aggression and substance abuse, deviant peer affiliation, peer rejection, and impulsiveness are targeted as risk factors. Targeted protective factors include empathy, problem-solving skills, school connectedness, assertiveness and adoption of conventional norms. The P3R: Stories of Us - Bullying program, composed of a series of film-based education will be used in the control schools. All 6th graders at each school will be recruited and followed for the three year study period. Students and teachers will complete self-report and nomination tasks. Growth curve analysis via hierarchical linear modeling (HLM;Bryk &Raudenbush, 1992) will be utilized to assess change in the major dependent variables (bullying, sexual harassment perpetration, dating aggression), structural equation modeling will test for mediators across the study period, and social network analysis will be instrumental in identifying peer norms and attitudes. PUBLIC HEALTH RELEVANCE: Sexual violence has been recognized to have dire and long lasting personal and public health consequences (World Report on Violence and Health, Jewkes, et al, 2002;CDC 2004;www.health.gov/healthypeople). Bullying, sexual harassment, and dating aggression appear to be related to the development of sexual violence across the lifespan. Bullying, sexual violence/harassment, and dating aggression have serious health consequences for youth, including significantly poorer mental and physical health, more trauma symptoms, and increased school avoidance. Despite common underlying risk factors, the development of bullying and sexual violence programs have remained largely divorced from each other- creating more burden and cost for schools. We will assess whether a comprehensive, skills- based violence prevention program has an impact on the risk and protective factors that are predictive of sexual violence, including sexual harassment and dating aggression. Our study will rigorously evaluate the impact of Second Step: Student Success Through Prevention, which targets the shared underlying risk and protective factors for bullying, hassrassment, and violence. This program is unique in its emphasis on the role of peer group norms, attitudes and behavior in the initiation and maintenance of bullying and other forms of sexual violence. However, individual and community factors are targeted and integrated into the curriculum as well.